Question

If we take four liquid water, glycerine, honey and cooking oil and put three drops of each together down a sloping surface and observe the time taken by each drop to reach the bottom. Which will come first?
(A) Water
(B) Cooking oil
(C) Glycerine
(D) honey

Answer 1

Hint : In order to find the correct option we can use the concept of viscosity here. Viscosity is defined as the measure of the resistance of a fluid to gradual deformation by shear or tensile stress. It also means the fluid’s resistance to flow. This property is related to fluids mainly.

Complete Step By Step Answer:
By using the concept of viscosity we know that water has the lowest viscosity out of all four. Thus, it will flow down the slope fastest.
Viscosity is the measure of the ease of flow of liquid. If the liquid follows easily then it is said to be less viscous.
The viscosity of a fluid is a measure of its resistance to deformation at a given rate.
The properties of viscosity are as follows;
Viscosity is a means of measurement of the movement of particles over one another.
It depends on the attractive force between the molecules.
Viscosity is dependent on the structural features of the molecules.
The viscosity of the liquid can be decreased by increasing the temperature.
Thus we can say that option A is correct which is water.

Note :
As mentioned earlier, the viscosity is a measure of the friction of fluids and there are two ways to measure a fluid’s viscosity, which are dynamic viscosity or absolute viscosity and kinematic viscosity. The SI unit of viscosity is the pascal second ( $Pa\cdots$ ) or $kg{\text{ }}{m^{ - 1}}{s^{ - 1}}$ .